1. Field of the Invention
The present invention relates to an air-conditioning apparatus for a vehicle adapted to execute a temperature adjustment within a vehicle interior according to a difference between a temperature in the vehicle interior and a set temperature, more specifically to an air-conditioning apparatus for a vehicle adapted to execute the temperature adjustment within the vehicle interior in consideration of an amount of solar radiation in the vehicle interior.
2. Description of Related Art
Conventionally, an air-conditioning apparatus used in a vehicle such as an automobile, for example, operates, when a difference between a temperature in a vehicle interior and a set temperature set by an occupant is large, under a transitional driving mode which uses, for example, a great air-blast volume and a blowing air temperature greatly different from the set temperature in order to approach rapidly the temperature in the vehicle interior to the set temperature. The air-conditioning apparatus operates, when the difference is less, under a stable driving mode configured to use, for example, a less air-blast volume and a blowing air temperature close to the temperature in the vehicle interior in order to maintain the temperature in the vehicle interior, because the vehicle interior is already comfortable.
Generally, a temperature to which the occupant feels differs greatly based on an amount of solar radiation contacting with the occupant even in the same temperature in the stable and transitional driving modes. Therefore, the amount of solar radiation in the vehicle interior is adopted as one of parameters for executing adjustment of the temperature in the vehicle interior, in the air-conditioning apparatus (for reference, see JPH5-124416A, pages 1 to 6, FIG. 1).
However, when the amount of solar radiation which is one of the parameters for executing the adjustment of the temperature in the vehicle interior changes rapidly and greatly as in an entrance and an exit of a tunnel, for example, the air-blast volume, the blowing air temperature and so on change rapidly. In this way, when the air-blast volume, the blowing air temperature and so on change rapidly, the occupant has felt uncomfortable in the stable driving mode.